In certain diseases, particularly in kidney diseases, water retention within an animal body presents serious difficulties. With total failure of the renal system, water build-up in the body, called edema, can lead to an accumulation in the blood of constituents normally eliminated in the urine, producing a severe toxic condition. This toxic condition can lead to death. The conventional treatment for diseases of this nature is periodic hemodialysis, where artificial kidney machines eliminate water and toxins from the body.
The cost of dialysis is exceedingly high and the availability of dialysis machines is not nearly as great as is convenient for both the practitioner and the patient involved. Additionally, the patient undergoing dialysis may suffer from significant physiological and mental discomfort. For these reasons, it is highly desirable to limit the frequency of dialysis to the minimum number of treatments necessary to preserve health.
Dialysis accomplishes two major objectives, viz. it removes both water and toxins from the body. The toxins are, primarily, substances resulting from protein metabolism. By proper control of the diet of the patient, particularly with regard to the amount of protein in the patient's diet, the necessary frequency of dialysis for removal of these toxins can be considerably reduced as compared to the frequency required with an unrestricted diet. However, unless the patient's consumption of water is severely limited, frequent hemodialysis is still necessary for the removal of water.
Restricting the patient's intake of water is generally very difficult, since patterns of water consumption are often deeply ingrained and changing these patterns may result in severe physical and mental discomfort to the patient. Many patients are not able to restrict their water intake to the minimum necessary for substantial reduction in the frequency of required dialysis.
Accordingly, if a method can be provided for removal of water from the body, then frequency of dialysis could be substantially reduced. Dialysis would, however, still be required for the periodic removal of protein derived toxins, but the frequency of dialysis for this purpose would be far less than the frequency normally required for the removal of both water and protein derived toxins.